Pros
The benefits package is competitive. The company and contracting environment is big enough to allow its staff to move into a variety of different positions over a career. Mid- and Senior-level managers are usually nicely seasoned and proficient with Program/Project Management. The company is good at winning new work - one of the "800 lb gorillas" in its markets.
Kontras
Systems/Engineering skills seem to be in short supply - the shortage tends to breed top-heavy teams and technical "heroes". Watch out for 401K vesting (4-5 years). From appearances, the company seems to periodically go on "hiring binges" to starve its competitors of talent in its markets, then many of those hired will sit on the bench consuming overhead funds for what could be a long time while they find positions. Then overhead eventually dries up and puts pressure on other areas. The company is not as good at keeping new and existing work as winning it. It can be politically difficult to move from one business unit to another within the company if you decide that you're out of place or need a change. Salaries seem to lag $5-$10K/yr or sometimes more behind current market.